Please check your internet connection and try again.
# Dicyclomine hydrochloride
## Overview
Dicyclomine is an antispasmodic and anticholinergic agent that acts by direct relaxation of smooth muscle in the gastrointestinal tract and by blocking acetylcholine at muscarinic receptors.
## Primary Indications
Functional bowel/irritable bowel syndrome (IBS).
## Adult Dosing
* **Initial:** 20 mg orally four times daily.
* **Titration:** After one week, may increase to 40 mg four times daily if tolerated.
* **Discontinuation:** If efficacy is not achieved after 2 weeks, discontinue therapy.
* **Maximum Dose:** 160 mg/day (40 mg qid).
## Pediatric Dosing
* **Safety/Efficacy:** Not established for use in pediatric patients. Use is generally avoided due to the risk of serious adverse effects, including respiratory distress and CNS stimulation in infants.
## Dose Adjustments
* **Renal/Hepatic Impairment:** No specific manufacturer guidelines provided; use with caution.
* **Geriatric:** Avoid in patients ≥65 years (Beers Criteria) due to high risk of anticholinergic side effects (confusion, urinary retention, constipation). If necessary, use the lowest effective dose.
## Contraindications
* Hypersensitivity to dicyclomine.
* Infants <6 months of age.
* Unstable cardiovascular status in acute hemorrhage.
* Myasthenia gravis.
* Obstructive disease of the GI tract (e.g., paralytic ileus, severe ulcerative colitis).
* Glaucoma.
* Severe obstructive uropathy (e.g., prostatic hypertrophy).
## Adverse Effects
* **Common:** Dry mouth, dizziness, blurred vision, nausea, drowsiness, nervousness, and somnolence.
* **Serious:** Heat prostration (due to decreased sweating), urinary retention, tachycardia, confusion, hallucinations (especially in the elderly), and anaphylaxis.
## Key Drug Interactions
* **Anticholinergics:** Synergistic effects (e.g., antihistamines, tricyclic antidepressants, antipsychotics) may significantly increase the risk of anticholinergic toxicity.
* **Potassium Chloride (Solid dosage forms):** Increased risk of GI mucosal lesions due to prolonged transit time.
* **Digoxin:** May increase digoxin absorption due to decreased GI motility.
## Monitoring
* Monitor for signs of anticholinergic toxicity: confusion, tachycardia, urinary retention, and constipation.
* Monitor GI symptoms for efficacy; discontinue if patient does not respond within 2 weeks.
## Clinical Pearls
* Dicyclomine is not for the treatment of peptic ulcer disease.
* It should be used with extreme caution in hot weather or during clinical exercise to avoid heatstroke, as the medication suppresses sweat production.
* Advise patients to avoid alcohol and CNS depressants, which may exacerbate drowsiness.
* Driving or operating machinery should be avoided until the patient knows how the drug affects them, as it may impair mental or physical abilities.
***
**Educational Disclaimer:** This information is for educational purposes only. Clinical practice protocols may vary by institution. Always verify dosages and contraindications against the current FDA-approved prescribing information, local institutional guidelines, and clinical drug databases (e.g., Lexicomp, Micromedex) before prescribing or administering medication.
